Tractor tread mechanism



a m Q N 5 Q S a 1 Q 3 Sheets-Sheet l Feb. 15, 1938. J JOY TRACTOR TREADMECHANISM Original Filed July 1, 1935 Feb. 15, 1938. OY 2,108,536

TRACTOR TREAD MECHANISM Original Filed July 1, 1935 5 Shets-Sheec 5 my.a

427 l x .425 45i {i' '44 r w '43 44 I LI "1 I) i W .40 1% l '41 L l; l 419 38 1 41019 11 37 I 3 J H ATTORNEY.

Patented Feb. 15, 1938 UNITED' STATES PATENT OFFICE TRACTOR ramMECHANISM Joseph F. Joy, Claremont, N. 11., assignor to SullivanMachinery Company, a corporation of Massachusetts 13 Claims.

This invention relates to tractor tread mechanism, and more particularlyto improvements in tractor tread driving, supporting and guidingstructure.

An object of this invention is to provide an improved tractor treadmechanism. Another object is to provide an improved guiding andcontrolling means for the tractor treads. A further object is to providean improved tractor tread driving means. A still further object is toprovide an improved means for varying the effective ground engagingsurface of the tractor treads, whereby engagement of the treads with thegroundsurface may be varied to facilitate turning of the machinesupported and propelled thereby. Still another object is to provide animproved means for increasing the effective area of the ground engagingsurface of the tractor treads whereby during operation of the machinesupported thereby, the treads may engage a relatively large area of theground surface to stabilize the machine during its operation. These andother objects and advantages of the invention will,

however, hereinafter more fully appear.

This application is a division of my copending application, Serial No.29,310, filed July 1, 1935.

In the accompanying drawings, there is shown for purposes ofillustration one form which the invention may assume in practice.

In these drawings,-

Fig. 1 is a plan view of a machine having embodied therein theillustrative form of the improved tractor tread mechanism.

Fig. 2 is a side elevational view of the machine shown in Fig. 1.

Fig. 3 is an enlarged view in longitudinal section taken substantiallyon line 3-3 of Fig. 1.

Fig. 4 is a horizontal sectional view .taken sub.- stantially on lineI-l of Fig. 3.

Fig. 5 is a cross sectional view taken substantially on line 55 of Fig.3.

Fig; 6 is a cross sectional view taken substantially on line 6-6 of Fig.3.

Fig. 7 is a horizontal sectional view taken substantially on line I-I ofFig. 2.

Fig. 8 is a detail sectional view taken online 8-8 of Fig. 3.

In this illustrative embodiment of the invention, the improved tractortread mechanism, generally designated I., is embodied in a coal miningmachine of the tractor tread supported and guided type, although it willbe evident that the improved tractor tread mechanism may be associatedwith machines of various other types.

The mining machine disclosed herein generally (Cl. lac-9.2)

comprises a base frame 2 supported by the tractor tread mechanism l, andin turn supporting a frame 3 on the forward end of which is mounted akerf cutting mechanism generally designated 4. The kerf cuttingmechanism comprises a rotatable head 5 carrying a cutter bar 6 havingmounted for circulation about its margin an endless cutter chain I; thecutter head being rotatable relative to the frame of the machine toposition the kerf cutter to cut plane kerfs in a mine wall in horizontaland vertical planes. Mounted on the frame 3 is a cable reel device,generally designated 8, for the power conductor cable, while supportedon the rearward portion of the base frame is a motor 9 for drivingthrough connections, clearly described in the above mentioned copendingapplication, the kerf cutting mechanism 5. As the particular structureof the mining machine does not enter into this invention, furtherdetailed description thereof is herein considered unnecessary.

The improved tractor tread mechanism I comprises tread frames IIIsupporting alined rear axles I I, II and a front axle I2, the treadframes III having cylindrical bearing portions I3, supporting bearingsleeves in which the rear axles I I, I I are journaled. Mounted inlongitudinal guideways I4 formed in the forward portions of the treadframes ID are adjustable bearing blocks l5 having adjusting screws l6and supporting bearings, in which is journaled the front axle II, in themanner c early shown in Fig. 4. The base frame 2 of the ing machine issupported by the tractor treads,and has cylindrical bearing portions I'Isupporting bearing sleeves alined with the alined bearing portions I3 ofthe tread side frames, and in which the alined rear axles II, I I arejournaled; the forward portion of the base frame having longitudinalslot-like openings I8 in the side walls thereof, through which the frontdrive sprockets 2|), 2!) respectively keyed to the alined rear axles II, II and front guide sprockets 2| keyed to the front axle I2. Thebearing blocks rection relative to the tread frames III, III to take upundue slack in the endless tread chains l9,' I9. The tractor-treadchains are driven each by a hydraulic motor 22 of a conventional design,secured to the opposite sides of the base frame 2 of the machine, andprojecting within the tractor treads between the top and bottom runs ofthe tread chains in the manner shown in Fig. 4. The power shaft 23 ofeach of these motors has keyed thereto a spur pinion 24 meshing with aspur gear 25 keyed to a horizontal, transversely extending shaft 26. Theshafts 26 are arranged in axial alinement, as shown in Fig. 4, and aresuitably journaled within the base frame 2 of the machine.

These alined shafts 26 project outwardly through the sides of the baseframe and have keyed thereto chain sprockets 21 engaging endless drivechains 28, in turn engaging chain sprockets 29 keyedto the alined rearaxles l I, II, respectively. The adjacent ends of the rear axles H, l lare splined at 30, and interlocked with the splineways of one axle is asliding clutch element 3i operated by a pivoted clutch shipper member32, and this clutch member is slidable axially from the position shownin Fig. 4 into interlocking engagement with the splineways on the end ofthe adjacent axle to connect the axles H, II for rotation together. Itwill thus be seen that when the axles I I, l i are connected together bythe clutch 3|, and'the motors 22, 22 are operated, the tractor treadsmay be simultaneously driven through the gearings 24, 25, shafts 2B, thechain and sprocket. connections 21, 28, 29, and the drive sprockets 23keyed to the rear axle. When the clutch 3! is shiftedto the positionshown in Fig. 4 to disconnect the axles, the tractor treads may beindependently driven through the driving connections.

Means is provided for varying the eifective area of the ground engagingsurfaces of the track laying treads so that the tread area may belessened when it is desired to turn sharply the machine by operating thetrack laying treads, and may be increased to provide a relatively wideground engaging surface to stabilize the machine during the cuttingoperation. The means for varying the ground engaging area of the tractorlaying treads comprises, for each tread, a bottom frame 35 pivotallyconnected at 36 to a horizontal pivot pin 31 supported by an upper guideframe 31'". A cooperating frame 38 is likewise pivotally mounted on ahorizontal pivot pin 39 supported by the adjacent upper guide frame, andthe adjacent ends of these frames 35 and 38 are pivotally con nectedtogether by pin and slot connections 40. As illustrated, the pivotedbottom frames 35 and 38 engage the lower runs of the track laying treadsand form the bottom supports for the tread frames and also cooperate toprovide bottom guides for the endless traction treads. Engaging the topsurface of each of the frames 38 is a plate 4| with which engages thelower end of a piston rod 42 of a piston 43 contained in a hydraulicjack cylinder 44 secured in a vertical position by a bracket 45 attachedto the inner side of the adjacent tread frame II). It will thus be seenthat when hydraulic pressure is supplied to the upper ends'of these jackcylinders, the latter are moved upwardly relative to the pistonscontained therein to move the pivoted frames 35, 38 about their pivotpins from the full line position shown in Fig. 3 to the lower dottedline position shown in that figure, thereby varying the area of contactof the track laying treads with the ground surface. It will be evidentthat since the pivoted members 35 and 38 and plates {:3 with whichground surface.

the piston rods 42 engage cannot move downwardly from the position shownin Fig. 2 due to the engagement of the treads with the ground surface.and therefore the cylinders and upper guide shaft 41 having keyedthereto, as shown in Fig. 3,

a spur gear 48 meshing with a spur gear 49 secured to the drive shaft 50Ma pump 5i. As illustrated, ,the pump 5! is arranged within a frame 3,the pump casing, in this instance, secured to the frame wall 53. Theintake of the pump 5| communicates with the reservoir .52, and thedischarge side of the pump is connected through suitable supply conduitsunder the conto effect propulsion of the machine in a straight path, therear drive axles I I, l l are connected together by the sliding clutch3| so that the track laying treads are driven in unison. When it isdesired to turn the machine in one direction orthe other, the clutch 3|is moved into its released position to disconnect the rear axles II, IIthereby, enabling independent drive and control of the track layingtreads by their individual driving motors 22, 22. To facilitate turningmovement of the machine, hydraulic pressure may be supplied to thehydraulic jacks 44, M for the tractor treads so that the pivoted treadguide frames 35, 38, may be swung downwardly about their pivots withrespect to the upper guide frames 31 from the full line position shownin Fig.3 to the dotted line position shown in that figure, therebydecreasing the contact area of the treads with the When the miningmachine is located in cutting position at the coal face, the hydraulicpressure is released from the tractor tread jacks 44 to move the pivotedguide frames into the position shown in Fig. 2, so that the relativelylarge surfaces of the tractor treads engage the mine floor to stabilizethe machine during the cutting operation. When the mining machine is incutting position at the coal face, the machine may be fed bodily towardand from the coal face by the tractor tread driving motors 22, these.motors being reversible and operable to drive the tractor treads at alow cutting speed. Under certain conditions, the track laying treaddriving motors may be independently operated to effect independentdriving of the track laying treads simultaneously in oppositedirections, thereby to swing the machine about a vertical axis to movethe cutter bar aboutsaid axis in a horizontal plane across the coal faceto effect a horizontal cut in the coal. Further uses and advantages ofthe improved tractor tread mechanism will be clearly apparent to thoseskilled in the art.

While there is in this application specifically described one form whichthe invention may assume in practice, it will be understood that thisorm i the some is shown for purposes of illus- 15 liquid containingreservoir 52 formed in the upper tration and that the invention may bemodified and embodied in various other forms without departing from itsspirit or the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent is: I

1. In a machine of the class described, propelling means comprisingendless traction treads and guiding means for said treads includingupper and relatively movable lower guide frame parts providing upper andlower elongated guideways for the upper and lower runs of the treads andalong which the treads are guided during their orbital movement, saidbottom guide frame parts connected together and cooperating to providesaid lower elongated guideways, means for individually or simultaneouslydriving said treads to propel and steer the machine, and meansassociated with each tread for moving the bottom guideframe parts withrespect to the upper guide frame parts to change the shape of saidbottom guideways thereby to vary the contact area of the ground engagingsurfaces of said treads, said last mentioned means being operable toeffect a decrease in the ground engaging surface area of the groundengaging portions of the treads to facilitate steering of the machine.

2. In a machine of the class described, propelling means comprisingendless traction treads and guiding means for said treads includingupper and relatively movable lower guide frame parts providing upper andlower elongated guideways for the upper and lower runs of the treads andalong which the treads are guided during their orbital movement, saidbottom guide'frame parts connected together and cooperating to providesaid lower elongated guideways, means for individually or simultaneouslydriving said treads to propel and steer the machine, and meansassociated with each tread for moving the bottom guide frame parts withrespect to the upper guide frame parts to change the shape of saidbottom guideways thereby to vary the contact area of the ground engagingsurfaces of said treads includ-' ing fluid operated Jacks one individualto each tread, and means for controlling the supply of fluid pressure tosaid jacks, said frame-partsmoving means being operable to effect adecrease in the ground engaging surface area of the ground engagingportions of the treads to facilitate steering of the machine.

3. In a mining machine, a' supporting frame, propelling and guidingmeans for said frame including endless traction treads. guiding meansfor said treads including upper and relatively movable lower guide frameparts providing elongated guideways for the upper and lower runs of thetreads during orbital movement of the latter, said bottom guide frameparts connected together and cooperating to provide said lower elongatedguideways, mechanism for independently or.

simultaneously driving said treads to propel and guide said supportingframe, and means associated with each tread for moving the bottom guideframe parts of the guiding means with respect to the upper guide frameparts to change the shape of the bottom guideways thereby to vary theeifective contact area of the ground engaging surfaces of said tractiontreads.

4. In a mining machine, a supporting frame, propelling and guiding meansfor said frame including endless traction treads, mechanism forindependently or simultaneously driving said treads to propel and guidesaid frame, and means associated with each tread for varying theefpivoted bottom guide frames.

ways for the lower runs of the treads and means.

for swinging said pivoted frames about their pivots to change the shapeof the bottom guideways;

5. In a machine of the character described, endless traction treads,tread guide frames for guiding said treads and including pivotallymounted, vertically swingable bottom tread guide frames cooperating toprovide elongated bottom guideways for the lower runs of the treads, andmeans associated with each tread and acting upon said pivoted guideframes to eifect swinging of the latter about their pivots to change theshape of the bottom guideways to vary the effective contact area of thetreads with the ground surface.

6. In a machine of the character described, endless traction treads,tread guide frames for guiding said treads and including upper sideframes and pivotally mounted, vertically swingable, bottom tread guideframes, the latter cooperating to provide elongate d bottom guidewaysfor the lower runs of the treads, and means associated with each treadand mounted on said side frames and acting upon said pivoted bottomguide frames to swing the latter about their pivots to change the shapeof the bottom guideways to vary the efl'ective contact area of thetreads with the ground surface.

'7. In a machine of the character'described, endless traction treads,tread guide frames for guiding said treads and including upper sideframes and pivotally mounted, vertically swingable, bottom tread guideframes, the latter cooperating to provide elongated bottom guideways forthe lower runs of the treads, and means associated with each tread andmounted on said side frames and acting upon with pivoted bottom guideframes to swing the latter about their pivots to change the shape of thebottom guideways to vary the effective contact area of the treads withthe ground surface, said bottom guide frame swinging means comprising apair of hydraulic jacks respectively acting upon said 8. In combination,'endless traction treads, tread guide frames including upper framemembers for guiding the upper runs of said treads and bottom guide"members for guiding the lower runs of the treads, the bottom guidemembers pivotally mounted on said upper guide frame members onhorizontal axes at their remote ends and pivotally connected together onaxes parallel with the guide member pivot axes. said pivoted guidemembers being swingable about their pivots in a vertical direction withrespect to said upper frame members. and means associated with eachtread and acting upon said pivoted guide members at points in adjacencyto their axes of pivotal connection for swinging said bottom guidemembers about their pivots at their remote ends relative to said upperguide frame members to vary the eifective contact area of the lower runsof the treads with the ground surface.

9. In combination, endless traction treads, tread guide frames includingupper frame members for guiding the upper runs of said treads and bottomguide members for guiding the lower runs of the treads, said bottom[guide members pivotally mounted on said upper guide frame members onhorizontal axes at their remote ends with the guide member pivot axes,said pivoted guide members being swingable about their pivots in avertical direction with-respect to said upper .vices mounted on theupper guide frame memframe members, and means associated with each treadand acting upon said pivoted guide members at points in adjacency totheir axes of pivotal connection for swinging said bottom guide membersabout their pivots at their remote ends relative to said upper guideframe members to vary the effective contact area of the lower runs ofthe treads with the ground surface, said swinging means including powerdebers and acting upon said lower guide members. 10. In combination,endless traction treads,

tread guide frames including upper frame mem-- bers for guiding theupper runs of said treads and bottom guide members for guiding the lowerruns of the treads, said bottom guide members pivotally mounted on saidupper guide frame members on horizontal axes at their remote ends andpivotally connected together on axes parallel with the guide memberpivot axes, said pivoted, guide members being swingable about theirpivots in a vertical direction with respect to said upper frame members,and means associated with each tread and acting upon said pivoted guidemembers at points in adjacency to their axes of pivotal connection forswinging said bottom guide members about their pivots at their remoteends relative to said upper guide frame members to vary the effectivecontact area of the lowerruns of the treads" with the ground surface,said swinging means including power devices mounted on the upper guideframe members and engaging said lower guide members, said power devicescomprising hydraulic cylinders mounted on said upper guide frame membersand pistons contained in said cylinders and operatively engaging saidpivoted guide members.

11. In combination, endless traction treads, tread guide framesincluding upper frame members for. guiding the upper runs of saidtreadsand bottom guide members for guiding the lower runs 01. said treads,thebottom guide memberspivotally mounted on said upper guide framemembers on horizontal axes at their remote ends, said bottom guidemembers being swingable about their pivots in a vertical direction withrespect to said upper frame members, and means acting upon said pivotedguide members'at points in adjacency to their adjacent ends for swingingsaid guide members about their pivots at their remote ends relative tosaid upper guide frame members to vary the effective contact area of thelower runs of the treads with the ground surface.

12. In combination, endless traction treads, tread guide framesincluding upper frame members for guiding the upper runs of said treadsand bottom guide members for guiding the lower runs of said treads, thebottomguide members pivotally mounted on said, upper guide frame memberson horizontal axes at their remote ends,

I said bottom guide members being swingable about their pivots inavertical direction with respect to said upper frame members, and meansacting upon said pivotedguide members at points in adjacency to theiradjacent ends for swinging said guide members about their pivots attheir remote ends relative tosaid upper guide frame members to vary theeffective contact area of" the lower runs of the treads with the groundsurface, said swinging means, including power devices mounted on theupper guide frame members and acting upon said lower guide members.

13. In combination, endless traction treads, tread guide framesincluding upper frame members for guiding the upper runs of said treadsand bottom guide members for guiding the lower runs of said treads, thebottom guide members pivotally mounted on said upper guide frame memberson horizontal axes at their'remote ends,

said bottom guide members being swingable about theirpivots in avertical direction with respect to said upper frame members, and meansacting upon said pivoted guide members at points in adjacency to theiradjacent ends for. swinging said guide members about their pivots attheir remote ends relative to said upper guide frame members to vary theeffective contact area of the lower runs of the treads with the groundsurface, said swinging means including power devices mounted on theupper guide frame members and engaging said lower guide members, saidpower devices comprising hydraulic cylinders mounted on said upper guideframe members and pistons contained in said cylinders and operatively.engaging said pivoted guide members.

JOSEPHVF. oy. I

CERTIFICATE OF CORRECTION.

- Patent No. 2,108,536.

JOSEPH. 3-. Jo

February 15, 19 I It is hereby certifiedthater-ror appears in theprinted specification of the abovanulbered patent requiring correctionas follows: Page 5 second column, line 1,2, claim 7, strike out thevvord "with"; and that the said Letters Patent should be read with thiscorrection therein that the same may conform to tho'record of the casein the-Patent Office.

Signed endvs ealed' this jth day or'x rn, A. n. 1938.

(Seal) Hem-y Van Arsdale, Acting Commissioner of Patents.

with the guide member pivot axes, said pivoted guide members beingswingable about their pivots in a vertical direction with-respect tosaid upper .vices mounted on the upper guide frame memframe members, andmeans associated with each tread and acting upon said pivoted guidemembers at points in adjacency to their axes of pivotal connection forswinging said bottom guide members about their pivots at their remoteends relative to said upper guide frame members to vary the effectivecontact area of the lower runs of the treads with the ground surface,said swinging means including power debers and acting upon said lowerguide members. 10. In combination, endless traction treads,

tread guide frames including upper frame mem-- bers for guiding theupper runs of said treads and bottom guide members for guiding the lowerruns of the treads, said bottom guide members pivotally mounted on saidupper guide frame members on horizontal axes at their remote ends andpivotally connected together on axes parallel with the guide memberpivot axes, said pivoted, guide members being swingable about theirpivots in a vertical direction with respect to said upper frame members,and means associated with each tread and acting upon said pivoted guidemembers at points in adjacency to their axes of pivotal connection forswinging said bottom guide members about their pivots at their remoteends relative to said upper guide frame members to vary the effectivecontact area of the lowerruns of the treads" with the ground surface,said swinging means including power devices mounted on the upper guideframe members and engaging said lower guide members, said power devicescomprising hydraulic cylinders mounted on said upper guide frame membersand pistons contained in said cylinders and operatively engaging saidpivoted guide members.

11. In combination, endless traction treads, tread guide framesincluding upper frame members for. guiding the upper runs of saidtreadsand bottom guide members for guiding the lower runs 01. said treads,thebottom guide memberspivotally mounted on said upper guide framemembers on horizontal axes at their remote ends, said bottom guidemembers being swingable about their pivots in a vertical direction withrespect to said upper frame members, and means acting upon said pivotedguide members'at points in adjacency to their adjacent ends for swingingsaid guide members about their pivots at their remote ends relative tosaid upper guide frame members to vary the effective contact area of thelower runs of the treads with the ground surface.

12. In combination, endless traction treads, tread guide framesincluding upper frame members for guiding the upper runs of said treadsand bottom guide members for guiding the lower runs of said treads, thebottomguide members pivotally mounted on said, upper guide frame memberson horizontal axes at their remote ends,

I said bottom guide members being swingable about their pivots inavertical direction with respect to said upper frame members, and meansacting upon said pivotedguide members at points in adjacency to theiradjacent ends for swinging said guide members about their pivots attheir remote ends relative tosaid upper guide frame members to vary theeffective contact area of" the lower runs of the treads with the groundsurface, said swinging means, including power devices mounted on theupper guide frame members and acting upon said lower guide members.

13. In combination, endless traction treads, tread guide framesincluding upper frame members for guiding the upper runs of said treadsand bottom guide members for guiding the lower runs of said treads, thebottom guide members pivotally mounted on said upper guide frame memberson horizontal axes at their'remote ends,

said bottom guide members being swingable about theirpivots in avertical direction with respect to said upper frame members, and meansacting upon said pivoted guide members at points in adjacency to theiradjacent ends for. swinging said guide members about their pivots attheir remote ends relative to said upper guide frame members to vary theeffective contact area of the lower runs of the treads with the groundsurface, said swinging means including power devices mounted on theupper guide frame members and engaging said lower guide members, saidpower devices comprising hydraulic cylinders mounted on said upper guideframe members and pistons contained in said cylinders and operatively.engaging said pivoted guide members.

JOSEPHVF. oy. I

CERTIFICATE OF CORRECTION.

- Patent No. 2,108,536.

JOSEPH. 3-. Jo

February 15, 19 I It is hereby certifiedthater-ror appears in theprinted specification of the abovanulbered patent requiring correctionas follows: Page 5 second column, line 1,2, claim 7, strike out thevvord "with"; and that the said Letters Patent should be read with thiscorrection therein that the same may conform to tho'record of the casein the-Patent Office.

Signed endvs ealed' this jth day or'x rn, A. n. 1938.

(Seal) Hem-y Van Arsdale, Acting Commissioner of Patents.

